It also matters to everyone everywhere whether China can sustain its economic growth as it exhausts its ready supplies of cheap labour, avoiding the traps into which some middle-income economies have stumbled. Yet even more than in other countries, the future of China’s foreign policy and its economy depend on the quality of decision-making produced by the political system. It’s the politics, stupid.

By now it is relatively clear what Xi is aiming to do. He is trying to steer a complex economy and society through difficult times by top-down changes, led and controlled by a purged, disciplined and reinvigorated Leninist party. He is doing this in unprecedented conditions for such a party, consciously trying to combine the “invisible hand” of the market with the “visible hand” of the party-state.

The “great helmsman” Mao Zedong is clearly one inspiration, but the pragmatic reformer Deng Xiaoping is another. “To reignite a nation, Xi carries Deng’s torch,” declared a commentary from the official news agency Xinhua.

Much of the reignition has so far been about establishing control over the party, state, military and what there is of civil society, after the Bo Xilai affair made apparent the internal crisis of party rule. Yet, as a hereditary communist, the president may genuinely believe enlightened, skilful authoritarian rulers can handle things best: Lenin’s wager, but also, in different variations, Plato’s and Confucius’s.

The sinologist Ryan Mitchell notes that in a 1948 article, a veteran Chinese communist called Xi Zhongxun was quoted as saying “the most lovable qualities of us Communist party folks are devotion and sincerity”. Speaking to party members in 2013, his son, Xi Jinping, said that “leading cadres must treat the masses with devotion and sincerity”.

This experiment is life-changing for the thousands of purged officials, who have disappeared into the tender embrace of the relevant party and state organs. (Being a senior Fifa official is light entertainment by comparison, even if some may miss their five-star Swiss breakfasts.)

It is also extremely uncomfortable for those Chinese who believe in free and critical debate, independent civic initiatives and non-governmental organisations. Here I found a striking contrast with earlier visits to Beijing. It’s not just the inconvenience of finding it difficult to access Gmail, Google docs and so much else on the internet. More seriously, I noticed a real nervousness among intellectuals who a few years ago were so outspoken; a sense that the boundaries of what can be said publicly are narrowing all the time.

Yes, that’s all true, say analysts of the “yes, Xi can” persuasion – and, if they are outside the system, they usually add that it is most regrettable. But, they say, look at the reform programme that is being pressed through with similar determination. Its key features are not easily summarised in familiar political and economic terms, because the Chinese mix is unique. For example, complex measures to address a dangerous overhang of local government debt, the introduction of property rights for agricultural land and changes to the household registration (hukou) system may be as consequential as anything that can be captured in a western headline.

If all this were to succeed as intended, western liberal democratic capitalism would have a formidable ideological competitor with worldwide appeal, especially in the developing world. For the west, there would be a silver lining: competition keeps you on your toes. I suspect the hubris of the early 2000s – both abroad, plotting regime change in Iraq, and at home, in the turbo-charged excesses of financial capitalism – had something to do with the lack of serious ideological competition.

This outcome is obviously not what I, as a liberal and a democrat, would wish for Chinese friends. But I do emphatically wish for them, and for ourselves, a China that experiences evolutionary and not revolutionary change. There are many reasons for that view, not least that most Chinese embrace it themselves. But the most important concerns nothing less than war and peace.

A communist regime in crisis would probably find it impossible to resist the temptation of playing the nationalist card more aggressively somewhere in its neighbourhood, building on decades of indoctrination, a selective interpretation of the recent past and a narrative of 150 years of national humiliation.

If China is already warning off US surveillance planes from flying over its artificial islands, imagine what it might do if it faced a systemic crisis. An armed conflict would not need to be directly between China and the US in order to be dangerous. However clear the “red lines” drawn by the US – and the lines should certainly be clearer than Barack Obama’s have been, in China’s interests as well as ours – the risk of miscalculation would be high.

Therefore, while this is not the evolutionary path that I and many others discerned and welcomed in China around the time of the Beijing Olympics, we must still hope that Xi’s leadership will manage to “cross the river by feeling the stones”.

My greatest concern flows not from the moral dictates of liberal democracy as personal preference, although it would be dishonourable to pretend that those don’t matter, but from the insights of political analysis that lead us to liberal democracy. Insights such as this: “If men were angels, no government would be necessary. If angels were to govern men, neither external nor internal controls on government would be necessary,” (James Madison, federalist paper No 51). Yes, dear comrades, it might be true, even though it was an American who said it.

In the short to medium term, it’s likely that Xi’s brand of smart authoritarianism will keep not just his party in power but the whole show on the road. That medium term could certainly span the two five-year periods which are all that is allowed for President Xi’s formal tenure of power – the Chinese Communist party having learned a lesson from the Soviet era of Leonid Brezhnev in a way that Fifa plainly has not.

There are so many significant power resources still at his disposal, including some genuine personal popularity and widespread national pride. I would therefore take a (small) bet that, in this narrow sense, “yes, Xi can” will prove correct. But in a broader sense and in the longer term? Watch out for a rocky 2020s.